Electric reflecting lamp



H. A. DOUGLAS July 17, 1928. 1,677,752

ELECTRIC REFLECTING Lu? Filed Jan. 27.. 1921 Patented July 17, 1928.

UNITED STATES HARRY A. DOUGLAS, QF BRONSON, MICHIGAN.

, ELECTRIC REFLECTING LAMP.

Application filed January 27, 1921. Serial 1101440388.. I

My invention relates to circuit continuing devices or connectors and also to focusing reflecting electric lamps including thepre- ,ferred embodiment of the invention in the "construction thereof. In carrying out one feature of my invention there is employed a main shell, a supplemental shell and a contact carrying body of insulation by and between the rear portion of the main shell and a front end portion of the supplemental shell, an arrangement that ensures the lo-' cation of a cdntact carrying disc or plug within an intermediate portion of a shel structure. WVhen my invention is embodied in a focusing electric lamp a shell structure is movable along the axis of the concave reflector and is brought into connection with a focusing rod that is operable at the back of the lamp by providing the rod with an inner head that is received between a rear end wall upon the shell structure and an ear formation struck from the side of the shell I structure and-extending into the bore of the shell.

I will explain my invention more fully by reference to the accompanying drawing showing the preferred embodiment thereof and in which Fig. 1 is a view in section, partially in elevation, of enough of a focusing reflecting electric lamp to reveal the application of my invention thereto; Fig. 2 is a sectional View on line 2--2 of Fig. 1; Fig. 3 is a View in elevation, with parts broken away,.of the focusing portion of the structure taken at right angles to the direction in which Fig. 1 is taken; and Fig. 4 is a sectional view on line 4-4 of Fig. 3.

Like parts are indicated by similar characters of reference throughout the different figures.

The reflecting electric lamp illustrated includes a concave reflector 1 and a concave back 2 spaced apart from the reflector. main metallic shell 3 passes through the rear end ofthe reflector and is slidable back and forth with respect to the reflector, the rear end of this main shell being within the space between-the reflector and the back.

An incandescent lamp 4 is provided with bayonet projections '5 that are rece1vable within the bayonet slots 6 formed in the front end of the main shell 3 whereby the incandescent lamp may be separably connected with the main shell.

The structure illustrated is aso-called single pole structure in which the lamp base constitutes a contact carrier that is provided with a central contact 7 upon its inner face and a metallic sheath 8 for electrical connection'with the metallic shell 3. The rear end of the main shell 3 is outwardly bulged to form an annular inner channel 9 that is U- shaped in cross section and receives a flange 10 upon the front end of the complemental shell 11. A contact carrying disc of insulation 12 is disposed in front of the flange 10 when the incandescent lamp is in place. The

contact 15 is connected by means of a conductor 16 with an outwardly spring pressed contact 17 that engages one terminal 18 of a supply circuit, this. terminal being mounted upon a plug 19 that is separably cou led with a shell 20- that is assembled wit the back 2 of the lamp. The conductor 16 passes through the other side of the shell 11 lnto connection with the contact 15 upon the-disk 12. This contact carrying plug 19 also carries another contact 21 connected .with the same terminal of the source of current with which contact-'18 is connected, this contact 21 being engaged by the outwardly spring pressed contact 22 that is connected with an inwardly spring pressed contact 23 engageable with the contact 24 upon the base of an auxiliary incandescent lamp 25.

The metallic sheaths about the bases of the tion with the metallic shells that receive these lamp bases, these shells being in suitable grounded connection with the source of current.

A incandescent lamps are in electrical connec- Whether or not the shell structure -is formed of assembled main and supplemental shells, it is preferably provided with a rear end wall 26 and two inturned ears 27 that are struck from the rear part of the shell. The focusing rod 28 has a head 29 which is gripped between the end wall 26 and the cars 27 so that as this rod is moved in and out the shell structure is moved therewith single plane of rotation with respect to the lamp. The nut may be provided with a screwdriver slot 32 to enable it to be turned and as the nut is confined to a single lane of rotation the rod 28v is moved inwar ly or outwardly according to the direction in which the nut is turned. Features not herein claimed form the subject matter of my. application Serial No. 554,271, filed April 17, 1922, a division of the present case.

While I have herein shown and particularly described the preferred embodiment of my invention I do not Wish to be limited to the precise details of construction shown as changes may readily be made without departing from the spirit. of my invention, but having tlius'described my invention I claim as new and desire to secure by Letters Pat- .ent the following:

An electrical connector including a shell having an annular internal groove which is U-shaped in cross section and which is located at one end of the shell; a second shell having a flange extending into said groove; a disk of insulation also received in said groove; and a spring contact carried by said disk adapted to be compressed by a circuit continuing element engaged in the first named shell and tending when so compressed to force the disk against the flange of the second shell whereby the possibility of disturbance of the assembly of said shells by vibration is eliminated.

In witness whereof I hereunto subscribe my name this 13th day of November A. D., 1920.

HARRY A, DOUGLAS. 

